The missile was launched around 10:30 p.m. EST this evening, and struck the satellite shortly after. Defense Secretary Robert Gates made the final decision to conduct the intercept.

Earlier in the day, it appeared that heavy seas around Hawaii would delay the intercept attempt. But the weather improved in the later afternoon, allowing the launch to proceed.

Pentagon officials say it may be a couple of days before the status of the fuel tank and its cargo are known. However, early reports suggested that the tank was destroyed by the missile impact.

It was, by any measure, an impressive test. Plans for the shootdown moved from the drawing board to execution in barely three months, after it became apparent that the dead spy satellite would soon reenter the earth's atmosphere.

The intercept was conducted by three U.S. Navy vessels, the cruiser Lake Erie and the destroyers Russell and Decatur. It is believed that the SM-3 that engaged the satellite came from the Lake Erie. All three ships had been modified for the shootdown mission.